In today's radio communications networks a number of different technologies are used, such as Long Term Evolution (LTE), LTE-Advanced, Wideband Code Division Multiple Access (WCDMA), Global System for Mobile communications/Enhanced Data rate for GSM Evolution (GSM/EDGE), Worldwide Interoperability for Microwave Access (WiMax), or Ultra Mobile Broadband (UMB), just to mention a few possible technologies for radio communications. A radio communications network comprises radio base stations providing radio coverage over at least one respective geographical area forming a cell. User equipments (UE) are served in the cells by the respective radio base station and are communicating with the respective radio base station. The user equipments transmit data over an air or radio interface to the radio base stations in uplink (UL) transmissions and the radio base stations transmit data over an air or radio interface to the user equipments in downlink (DL) transmissions.
Each radio base station may comprise one or more antennas used for communicating in the cell. In any radio communications network, a problem with an antenna causing the antenna not to work properly is a significant cause of performance degradation of the radio communications network. A problem with an antenna may be caused by mechanical failures, faulty installation, storm effects or normal wear and tear, resulting in that the antenna will become misaligned or the antenna gain will degrade. An antenna with a problem may be referred to as a faulty antenna. Today, a faulty antenna may be hard to detect or trouble-shoot, as the communication within the cell served by the radio base station with the faulty antenna will continue to work. However, the performance of the radio communications network will suffer due to e.g. coverage holes, and/or increased interference. In e.g. 3rd Generation Partnership Project (3GPP) LTE today there is no dedicated function for detecting a faulty antenna, except for total loss of an antenna.